# SPDX-License-Identifier: GPL-2.0
#
# checkincludes: find/remove files included more than once
#
# Copyright abandoned, 2000, Niels Kristian Bech Jensen <[email protected]>.
# Copyright 2009 Luis R. Rodriguez <[email protected]>
#
# This script checks for duplicate includes. It also has support
# to remove them in place. Note that this will not take into
# consideration macros so you should run this only if you know
# you do have real dups and do not have them under #ifdef's. You
# could also just review the results.

use strict;

sub usage {
    print "Usage: checkincludes.pl [-r]\n";
    print "By default we just warn of duplicates\n";
    print "To remove duplicated includes in place use -r\n";
    exit 1;
}

my $remove = 0;

if ($#ARGV < 0) {
    usage();
}

if ($#ARGV >= 1) {
    if ($ARGV[0] =~ /^-/) {
        if ($ARGV[0] eq "-r") {
            $remove = 1;
            shift;
        } else {
            usage();
        }
    }
}

my $dup_counter = 0;

foreach my $file (@ARGV) {
    open(my $f, '<', $file)
        or die "Cannot open $file: $!.\n";

    my %includedfiles = ();
    my @file_lines = ();

    while (<$f>) {
        if (m/^\s*#\s*include\s*[<"](\S*)[>"]/o) {
            ++$includedfiles{$1};
        }
        push(@file_lines, $_);
    }

    close($f);

    if (!$remove) {
        foreach my $filename (keys %includedfiles) {
            if ($includedfiles{$filename} > 1) {
                print "$file: $filename is included more than once.\n";
                ++$dup_counter;
            }
        }
        next;
    }

    open($f, '>', $file)
        or die("Cannot write to $file: $!");

    my $dups = 0;
    foreach (@file_lines) {
        if (m/^\s*#\s*include\s*[<"](\S*)[>"]/o) {
            foreach my $filename (keys %includedfiles) {
                if ($1 eq $filename) {
                    if ($includedfiles{$filename} > 1) {
                        $includedfiles{$filename}--;
                        $dups++;
                        ++$dup_counter;
                    } else {
                        print {$f} $_;
                    }
                }
            }
        } else {
            print {$f} $_;
        }
    }
    if ($dups > 0) {
        print "$file: removed $dups duplicate includes\n";
    }
    close($f);
}

if ($dup_counter == 0) {
    print "No duplicate includes found.\n";
}